This type of the double-coated adhesive tape has been increasingly and widely used in recent years, because it is capable, unlike conventional double-coated adhesive tape, to have the adhesive effect only by the adhesive substance with no core material and because ideal adhesive results can be obtained by the property of adhesive substance only.
In the following, an example of this invention is explained with reference to the accompanying drawings:
In FIG. 8, 101 indicates a transferring device, comprising a tape roll support shaft 103 mounted in a casing 102, on which a tape roll 106 is rotatably supported. The tape roll takes up a double-coated adhesive transferring tape, wherein pressure sensitive adhesive substance 105 is coated on one face 104a of the double-sided released paper 104. The tape is rolled on the tape roll support shaft in such manner that the surface coated with the adhesive substance faces outward. Further, a pressure plate 107 similar to a plate spring is mounted inside the casing 102 in the direction opposite to the rotating direction of said tape roll, applying the braking force in such degree as to block free rotation of said tape roll 106. In this figure, 108 shows an exposed portion of the tape, and 109 is an outlet of the double-coated released paper 104, on which the adhesive substance 105 has been released and transferred.
The automatic transferring device for the double-coated adhesive transferring tape with the construction as explained above causes no particular problem so far as the user applies an even force on tape surface and presses it positively on the article to be transferred unless the double-sided released paper is slackened and caught in the space under the outlet of said released paper as shown in FIG. 8. However, if tape is run with its surface inclined, the adhesive substance is forced to remain on the double-sided released paper, blocking the smooth contact rotation thereof with the pressure plate or obstructing the discharge of the released paper from the outlet. For this reason, it is necessary to acquire a sort of skill until the user becomes able to use it without trouble. Because the pressure plate is disposed to the direction opposite to the rotating direction of the double-sided released paper, the tape roll receives relatively big resistance during rotation. This is often likely to cause the slackening of the tape even when the adhesive substance remaining on the double-sided release paper does not stick. The slackening further causes the tape to sag and hinders the rotation of the tape at the position, where it contacts with the pressure plate, which faces opposite to the rotating direction of the tape roll, making it impossible to transfer the adhesive substance in the smooth and constant conditions. In addition, it is extremely difficult to have the casing straightly faced toward the surface to be transferred. When it is run in inclined position, the adhesive substance is not uniformly transferred to the desired surface, and the adhesive effects are not obtained as desired.
There have been the following problems in the double-coated adhesive transferring tape itself, used in the automatic transferring device for this type of adhesive tape:
In recent years, double-coated adhesive transferring tape has been extensively used, wherein a sheet of double-sided released paper is coated with adhesive film and is rolled up in the shape of a tape roll. Compared with the conventional type of double-coated adhesive transferring tape, using a core material, this new type of double-coated adhesive transferring tape is a simple but ideal type of tape, while the following problems still remain unsolved:
Because adhesive substance film is coated all over the upper surface of the double-sided released paper, the adhesive substance tends to protrude to both sides when the paper is rolled up into the shape of tape. For instance, when this tape roll is used within the casing of the automatic transferring device, the protruding adhesive substance sticks to the inner surface of the casing and hinders the smooth and perfect rotation and feeding of the double-coated adhesive transferring tape. At the same time, the adhesive substance stuck on inner surface of the casing is often separated, resulting in the pressure sensitive transfer of the double-coated adhesive transferring tape, which now partically lacks the adhesive substance. In the course of transition and adhesion to the desired position of this type of double-coated adhesive transferring tape, the adhesive tape is cut off by strongly pressing the automatic transferring device and by raising it to the desired position. This requires, however, a considerable degree of skill and force, and fatal defects are often caused such as the defect, wherein the tape is not properly cut off at the desired position, resulting in the raising of the tape together with the automatic transferring device and in the separation of the stuck portion of the tape, or the defect, wherein the desired end portion is not disposed in good order. In order to eliminate such defects, it was proposed to arrange the pieces (patches) of adhesive substance consisting of adhesive film on the double-coated released paper--lengthwise in the continuous manner each with a certain intermediate space--where the double-coated released paper was sometimes exposed in the longitudinal direction. According to the present improvement, the adhesive tape is incorporated in the automatic transferring device as a tape roll and is used as a direct pressure sensitive roller. Because adhesive substance is not coated in the intermediate space between the patches of the adhesive substance, the disadvantageous condition of the tape is now eliminated, where the tape could not be cut off even when it is strongly pressed and then pulled up. The desired width of the double-coated adhesive transferring tape can now be transferred and adhered in simple manner. At the same time, the adhesive substance can be transferred and adhered to the desired end portion, and there is no possibility that the adhesive substance is turned to liquid state or it becomes uneven in thickness as often experienced in the prior method of pressing and cutting.
Even in this type, however, there remains the possibility that the adhesive substance may protrude from the sides when the tape roll is placed in the automatic transferring device and that it sticks to the inner surface of the automatic transferring device, hindering the perfect rotation and feeding of the tape because the adhesive substance is coated on the upper side and lower side of the patches of adhesive substance in the longitudinal direction.